In manufacturing of an electronic device such as a semiconductor device, a processing apparatus is used. In general, the processing apparatus includes a chamber body, a pedestal, and a gas supply portion. The pedestal is provided in the chamber body. The pedestal includes a main body on which a workpiece is to be placed, and a cooling table in which a passage for a refrigerant is formed therein. The main body is provided on the cooling table. In addition, a heater is built in the main body. The gas supply portion supplies gas for processing a workpiece into the chamber body.
In processing of the workpiece using the processing apparatus, the temperature of the workpiece may be set to a high temperature over, for example, 200° C. To this end, a pedestal having a structure which increases thermal insulation properties between the cooling table and the main body is proposed in Japanese Patent No. 5482282.
The pedestal described in Japanese Patent No. 5482282 includes a plurality of thermal insulation members in addition to the cooling table and the main body. The thermal insulation members are provided between the cooling table and the main body. Accordingly, in the pedestal described in Japanese Patent No. 5482282, the thermal insulation members and spaces provided between the thermal insulation members are interposed between the cooling table and the main body. Therefore, it is possible to set the temperature of the main body to a high temperature.
Meanwhile, in a pedestal, an electrostatic chuck may be provided on a cooling table. In general, the cooling table and the electrostatic chuck are bonded to each other by an adhesive agent. In such a pedestal, a distribution of a temperature of the electrostatic chuck is required to be adjusted in a radial direction with respect to the center axis of the electrostatic chuck. To this end, typically, a plurality of heaters are coaxially provided within the electrostatic chuck.
In the pedestal, a range of a settable temperature of the electrostatic chuck is narrow. In addition, a range of a settable temperature increase rate of the electrostatic chuck and a range of a settable temperature decrease rate of the electrostatic chuck are also narrow. Further, it is difficult to set a temperature distribution which greatly varies in the radial direction with respect to the electrostatic chuck.